考虑列车运行速度的应答器传输系统可靠性评估

摘要

为定量评估应答器传输系统的可靠性,分析列车运行速度对系统可靠性评估的影响,提出基于马尔可夫过程的可靠性评估方法.将应答器传输模块BTM报文层不能正确译码的概率作为系统可靠性评估的指标,采用鱼骨图法将影响系统可靠性评估的因素分为动态因素与静态因素,分析列车运行速度对BTM接收报文比特数及误比特率的影响,并对可靠性评估方法进行仿真验证.结果表明:列车运行速度主要通过影响BTM接收报文比特数来影响系统的可靠性;当BTM接收报文为应答器安全报文长度的整数倍时,BTM报文层不能正确译码的概率存在拐点;拐点的变化率随着整数倍数的增大而减小,随着BTM接收报文误比特率的减小而增大.%To evaluate the reliability of balise transmission system quantitatively , and analyze the influence of train velocity on system reliability evaluation , a reliability evaluation method based on Markov process was proposed.The probability that the message layer of balise transmission module(BTM) can not be correctly de-coded was used as an index of system reliability evaluation . The Ishikawa diagram method was used to classify the factors that affect the system reliability evaluation into dynamic and static factors , to analyze the influence of train speed on the number of message bits received by BTM ,and the bit error rate . The evaluation method was verified finally . The results show that system reliability is affected by train velocity mainly through the number of bits available for BTM .When the message received by BTM is an integral multiple of telegram win-dow bits ,an inflection point is observed in the probability that the BTM msessage layer can not decode correct-ly . The change rate of the inflection point decreases with the increase of integral multiple . The change rate of the inflection point increases with the decrease of the bit error rate of the message received by BTM .